The present invention relates to a modified nebulizing device for generating a nasal continuous positive airway pressure (CPAP) and addition of nebulized drug which can be carried out simultaneously and in synergy without loosing a substantial amount of nebulized drug. Further, the present invention also discloses a nebulizing device and a modified nebulizing CPAP device usable in a system for generating a continuous positive airway pressure (CPAP) and simultaneously and in synergy adding of nebulized drug without loosing a substantial amount of nebulized drug.
There exists devices for generating a continuous positive airway pressure. Such a device is disclosed in EP-B1-0447 443.
It is known that in respiratory treatment of neonates additional treatment with drug is often required. Today use of ancillary masks with upstream drug atomizers are known but then the respiratory treatment of neonates has to be interrupted. U.S. Pat. No. 7,047,968 discloses a nasal CPAP device wherein the drug flow is introduced via a second opening directed into a hollow body and via a first opening is the respiratory gas flow introduced. However, a problem when introducing the drug in this way is that air stream that generates the pressure blows against the hole in the small hollow body and a part of this air stream washes out the hollow body and takes part of the nebulized drug out through the pressure generating hole and also causes a dilution of the drug which is being introduced into the hollow body. U.S. Pat. No. 7,047,968 introduces a nasal CPAP device in such a way that respiratory treatment of neonates does not have to be interrupted to provide additional treatment with drug. Experiments has been carried out using a device as disclosed in EP-B1-0447 443 wherein the drug flow is introduced via the inlet channel for fresh gas. This results in the similar problem as above. Another problem is that the drug particles introduced as disclosed above falls out as liquid and do not remains aerosolized during the transport in the tube and thus never reaches the subjects airway or lungs.
If nebulized drug is introduced via the expiratory channel most of the nebulized drug is lost almost instantly. Further, if the pressure gauge measuring tube is replaced with a wider tube enough amount of nebulized drug is introduced but the main part of said nebulized drug would be lost through the expiratory channel. The reason for this is that nebulized drug is introduced in the part where pressure generation is taking place and where it is severe turbulence. During most of subjects respiratory cycle is it also at this point a greater inflow than the subjects respiratory volumes and the flow is thus mostly directed away from the child which will blow the nebulized drug away.
Therefore there is a need within the technical field of CPAP and administrating nebulized drug to solve the problem that most of the introduced nebulized drug does not reach the subjects airway, lungs or pulmonary alveolus.